Having set my mind at rest in Part 1 that my new lens wasn’t totally dodgy, I set about trying to make it even better. In fact, I decided to repeat the process on all three of my main lenses. (more…)
Posts Tagged ‘testing’
Canon Lens Auto Focus Accuracy – Part 2
Sunday, August 21st, 2011Canon Lens Auto Focus Accuracy – Part 1
Sunday, August 14th, 2011Back in May I wrote about the new Canon 70-200mm f4 L IS lens I had chosen and my reasons for making the choice I did. After taking it out on a few non-critical sessions I haven’t been blown away by its sharpness – it’s good, but perhaps not quite as crisp as I was hoping for. I started wondering if this was down to my unrealistic expectation or if there was something wrong with the lens.
Then one day I was out on the riverbanks in Durham and saw a heron fishing in the shallows. I was a bit far away, but thought I’d grab a few frames just for interest. Reviewing the shots I’d just taken zoomed in on the camera’s LCD, the heron was clearly blurred even though I was absolutely certain I had auto-focused on the body (I was too far away to pick up the eye which I would normally aim for). What was more, the detail in the background was sharp – and it was consistent, shot after shot. Suddenly I panicked – did my new lens have a serious back-focus problem?